methyl 6-oxohexanoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The cleavage in stage (c) is advantageously carried out in the presence of molecular oxygen or a gas which contains molecular oxygen and an inert gas, such as nitrogen, carbon dioxide, argon or steam. A molar ratio of formylvaleric esters to molecular oxygen of from 1:0.05 to 1:3, in particular from 1:0.2 to 1:1.5, e.g., from 1:0.25 to 1:1.25, is advantageously used. This increases the catalyst life and in particular the yield of pentenoic esters. The presence of molecular oxygen was not indicated since methyl 5-formylvalerate is oxidized to monomethyl adipate in a yield of 96% by molecular oxygen at as low as 50° C., as disclosed in European Patent 131,860, and it was therefore to be expected that 4- and 3-formylvaleric esters would be oxidized in a similar manner to give 2-methylglutaric acid and 3-ethylsuccinic esters. This increases the catalyst life

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Glycinamide hydrochloride (6.73 g, 0.061 mol) and methyl 6-oxohexanoate (8.8 ml, 0.061 mol) were reacted together according to the procedure of example 2, to give 0.93 (7.6%) of the title compound, m.p. 58°-60° C. (with decomposition). NMR (DMSO-d6): deltaH =8.10 (b.s., 1H, CONH); 4.50-4.15 (c.a., 1H, NHCHNH); 3.55 (s, 3H, COOCH3); 3.20 b.s., 1H, CH2NHCH); 3.05 (s, 2H, NHCH2CO); 2.45-2.10 (c.a., 2H, CH2COO); 1.80-1.10 (c.a., 6H, CH2CH2CH2CH2COO). MS (E.I., 70 eV, 1.5 mA) m/z=200 (M+), 169 (M--OCH3)+, 85 (C3H5N2O)+.

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: An ε-caprolactam preparation process starting from methyl 5-formylvalerate is described in U.S. Pat. No. 4,730,040. In this process, methyl 5-formylvalerate is first hydrolyzed (step x) in the presence of water and an acidic agent to yield 5-formylvaleric acid. The acid is then further reacted (step y) in aqueous solvent with ammonia and hydrogen in the presence of a Raney nickel catalyst in one reaction step to yield 6-aminocaproic acid. After separation of ammonia, the aqueous mixture is heated to 300° C. (step z) to form ε-caprolactam by cyclization of the 6-aminocaproic acid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: An ε-caprolactam preparation process starting from methyl 5-formylvalerate is described in U.S. Pat. No. 4,730,040. In this process, methyl 5-formylvalerate is first hydrolyzed (step x) in the presence of water and an acidic agent to yield 5-formylvaleric acid. The acid is then further reacted (step y) in aqueous solvent with ammonia and hydrogen in the presence of a Raney nickel catalyst in one reaction step to yield 6-aminocaproic acid. After separation of ammonia, the aqueous mixture is heated to 300° C. (step z) to form ε-caprolactam by cyclization of the 6-aminocaproic acid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Glycinamide hydrochloride (6.73 g, 0.061 mol) and methyl 6-oxohexanoate (8.8 ml, 0.061 mol) were reacted together according to the procedure of example 2, to give 0.93 (7.6%) of the title compound, m.p. 58°-60° C. (with decomposition). NMR (DMSO-d6): deltaH =8.10 (b.s., 1H, CONH); 4.50-4.15 (c.a., 1H, NHCHNH); 3.55 (s, 3H, COOCH3); 3.20 (b.s., 1H, CH2NHCH); 3.05 (s, 2H, NHCH2CO); 2.45-2.10 (c.a., 2H, CH2COO); 1.80-1.10 (c.a., 6H, CH2CH2CH2CH2COO). MS (E.I., 70 eV, 1.5 mA) m/z=200 (M+), 169 (M--OCH3)+, 85 (C3H5N2O)+.